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1.
ABSTRACT. The butterfly assemblages of three vegetation types (pasture, heathland and rocky outcrop with Genista spp.) and two geographical orientations (a northern slope and a sheltered gorge) were studied along an altitudinal gradient in the Picos de Europa in northern Spain. In order to study the effects or historical climatic changes on current butterfly assemblages, it was examined if changes in richness and faunal composition of assemblages were joined with changes in their biogeographical composition. The three vegetation types showed characteristic butterfly assemblages, but no difference in species richness and biogeographical composition was found. Species richness in the sheltered gorge was higher than in the northern slope. Faunal composition also varied between orientations and there were more widespread and Mediterranean species in the sheltered gorge than in the northern slope. Species richness declined with increasing altitude, though a midaltitudinal peak was observed. There was a faunal segregation between high and low localities. Species richness of widespread and Mediterranean butterflies decreased as altitude increased, whereas the reverse was true for montane species. Moreover, biogeographical elements differed in their climatic tolerances measured as altitudinal ranges. Therefore, changes in richness and composition of butterfly assemblages between both slopes and along the altitudinal gradient were joined in part with variation in their biogeographical composition. These results suggest that current species richness and composition of butterfly assemblages in the Picos de Europa might be the consequence of differential colonization of refuges during the past climatic changes. 相似文献
2.
The influence of salinity on the growth, gross chemical composition and fatty acid composition of three species of marine microalgae,Isochrysis sp.,Nannochloropsis oculata andNitzschia (frustulum), was investigated. There was no significant change in growth rate ofIsochrysis sp. andN. (frustulum) over the experimental range of salinity (10–35 ppt), whileN. oculata had a significantly slower growth rate only at 35 ppt. The ash content of all three species increased with increasing salinity. Two species,Isochrysis sp. andN. oculata, showed significant linear increases in total lipid content with increasing salinity over the range 10 to 35 ppt.N. (frustulum) showed significant linear decrease in total lipids, with the highest percentage at low salinity within the range 10–15 ppt. Variation in salinity had only a slight effect on the total protein, the soluble carbohydrate and chlorophylla content of all species. All species responded to change in salinity by modifying their cellular fatty acid compositions. Significant positive correlations were observed between increase in salinity and increase in the percentage ofcis-9-hexadecenoic acid [16:1 (n-7)] over the entire experimental range inN. (frustulum) and between 25–35 ppt inN. oculata. There were curved relationships between salinity and percentage of hexadecanoic acid [16:0] inN. oculata andN. (frustulum), with maxima within the range 25–30 ppt for both species. A curved relationship was found between salinity and percentage of eicosapentaenoic acid [20–5(n-3)], forN. (frustulum), with lowest percentages of the fatty acid within the range 25–30 ppt. There was no consistent pattern in the percentages of other major fatty acids as functions of salinity. The Northern Territory isolateN. (frustulum) was unusual in having a substantial increase in total fatty acids with decreasing salinity (85 mg g–1 dry wt at 10 ppt compared with 33 mg g–1 at 35 ppt). The optimum salinities for the production of maximum amount of lipids and the essential fatty acids 20:5(n-3) and/or 22:6(n-3) were as follows:25 ppt forIsochrysis sp. [22:6(n-3)]; 20–30 ppt forN. oculata [20:5(n-3)]; 10–15 ppt forN. (frustulum) [20:5(n-3) and 22:6(n-3)].Author for correspondence 相似文献
3.
We have investigated the genetic population structure within and the genetic differentiation between local populations of the large blue butterfly Maculinea alcon throughout the Jutland peninsula. Samples were collected as eggs on foodplants (Gentiana pneumonanthe), and reared to 4th instar caterpillars in the laboratory. A significant excess of homozygotes was found for all the investigated allozyme loci in most of the populations. A North-South cline was observed for the allele frequencies at some of the loci and for several linkage groups. Because some of the allele frequency clines were parallel to clines in adult morphological variation, we interpret our results as evidence for the co-existence of at least two gene pools within the Danish Maculinea alcon populations. Multilocus electrophoretic data revealed highly positive but variable FST values, which under this scenario would reflect varying frequencies of the Maculinea gene pools across the local populations. The significantly positive FIS values indicate that these gene pools are at least partly reproductively isolated (Wahlund effect). The co-occurrence of several Maculinea alcon gene pools on many local sites in Jutland is of great importance for conservation of the fragmented Maculinea populations. Our results show that there is probably more Maculinea biodiversity to conserve than was previously thought, and suggests that extant populations are more fragmented and vulnerable than counts of flying adults or eggs on foodplants indicate. 相似文献
4.
5.
Abstract. 1. Mating patterns in a natural population of checkerspot butterflies, Euphydryas editha Boisduval, were investigated by dusting male external genitalia with fluorescent dyes and examining mated females under UV light.
2. These dyes may have diverse applications in studies of insect populations. 相似文献
2. These dyes may have diverse applications in studies of insect populations. 相似文献
6.
Twelve species of microalgae, isolated from north Australian marine, freshwater and hypersaline environments, were grown under controlled conditions of temperature, pH, photon flux density and salinity, and analysed for ash, total protein, water soluble carbohydrates, chlorophylla, total lipids, total fatty acids and fatty acid composition. Highest levels of the polyunsaturated fatty acid eicosapentaenoic acid [20:5(n-3)] were found in the marine diatoms.Nitzschia (frustulum) andN. closterium (23.1% and 15.2% of total fatty acids, respectively). None of the species studied had levels of docosahexaenoic acid [22:6(n-3)] greater than 1.1 % of total fatty acids. None of the chlorophyte species contained significant levels of either 20:5(n-3) or 22:6(n-3). The highest total fatty acid concentration of all species in the study was found in the freshwater chlorophyte speciesScenedesmus dimorphus (105 mg g–1 dry wt). The hypersaline speciesDunaliella salina had the highest total lipid content (28.1% dry wt), followed byN. closterium, N. (frustulum) andNavicula sp. (24.2–27.8% dry wt).Chlamydomonas sp. had the highest protein content (66.9% dry wt).N. (frustulum) was highlighted as a possible useful source of lipids and polyunsaturated fatty acids in mixed microalgal diets for mariculture organisms used in tropical aquaculture.Author for correspondence 相似文献
7.
黑莓汁的理化特性及贮藏期营养成分的变化 总被引:10,自引:1,他引:10
对黑莓浓缩汁的理化特性及其营养成分变化进行研究,结果表明:pH3~4,波长511~514nm时,果汁色泽最佳;果汁抗氧化还原能力很弱,但具有很强的光和热的稳定性。0~4℃低温贮藏1年后,6种维生素的损失率都超过50%;含糖量损失407%;SOD活性和氨基酸含量分别损失10%和124%;含酸量略有增加 相似文献
8.
麻竹材化学成分的变异 总被引:3,自引:0,他引:3
麻竹(DendrocalamuslatiflorusMunro)是我国南方著名笋竹两用竹种,竹秆粗大通直,大量用于制浆造纸,是我国纸浆材培育的主要竹种之一。化学成分是研究竹材材性的基础和竹材利用的依据。有关麻竹材化学成分的研究未见报道。本文应用正交试验方?.. 相似文献
9.
Species richness of phytoplankton of the Pitchavaram mangals was high. There were 82 species constituted by 67 species of diatoms, 12 species of dinoflagellates and 3 species of bluegreen algae. The diatoms formed the bulk with 72% followed by the dinoflagellates with 15%, in which there were autochthonous (temporary and permanent) and allochthonous forms. Phytoplankton population density exhibited a wide seasonal fluctuation with the minimum during monsoon and the maximum during summer, suggesting the possible differential influence of various environmental factors. 相似文献
10.
BACKGROUND AND AIMS: Floral nectaries and nectar features were compared between six Argentinian Ipomoea species with differences in their pollinator guilds: I. alba, I. rubriflora, I. cairica, I. hieronymi var. hieronymi, I. indica, and I. purpurea. METHODS: Pollinators were recorded in natural populations. The morpho-anatomical study was carried out through scanning electron and light microscopy. Nectar sugars were identified via gas chromatography. Nectar production and the effect of its removal on total nectar sugar amount were determined by using sets of bagged flowers. KEY RESULTS: Hymenopterans were visitors of most species, while hummingbirds visited I. rubriflora and sphingids I. alba. All the species had a vascularized discoidal nectary surrounding the ovary base with numerous open stomata with a species-specific distribution. All nectar samples contained amino acids and sugars. Most species had sucrose-dominant nectars. Flowers lasted a few hours. Mean nectar sugar concentration throughout the lifetime of the flower ranged from 34.28 to 39.42 %, except for I. cairica (49.25 %) and I. rubriflora (25.18 %). Ipomoea alba had the highest nectar volume secreted per flower (50.12 microL), while in the other taxa it ranged from 2.42 to 12.00 microL. Nectar secretion began as soon as the flowers opened and lasted for a few hours (in I. purpurea, I. rubriflora) or it was continuous during the lifetime of the flower (in the remaining species). There was an increase of total sugar production after removals in I. cairica, I. indica and I. purpurea, whereas in I. alba and I. rubriflora removals had no effect, and in I. hieronymi there was a decrease in total sugar production. CONCLUSIONS: The chemical composition, production dynamics and removal effects of nectar could not be related to the pollinator guild of these species. Flower length was correlated with nectary size and total volume of nectar secreted, suggesting that structural constraints may play a major role in the determination of nectar traits of these species. 相似文献
11.
Dipierri JE Alfaro EL Scapoli C Mamolini E Rodriguez-Larralde A Barrai I 《American journal of physical anthropology》2005,128(1):199-209
In order to study the isonymic structure of Argentina, the surname distributions of 22.6 million electors registered for the year 2001 were analyzed in the 24 districts (distritos) and 541 municipalities (municipios) of the country. The number of different surnames found was 414,441. Matrices of isonymic distances between districts were constructed and tested for correlation with the geographic distance between the capital towns of the districts. We found that, for the whole of Argentina, Euclidean distance was correlated with the log of geographic distance (r=0.480+/- 0.067). A dendrogram of the 24 regions was built from the matrix of Euclidean distances, using the UPGMA method. The clusters identified by the dendrogram are coincident with conterminous geographical regions of the country. Random inbreeding calculated from isonymy, F(ST), was highest in La Rioja, Corrientes, and Santiago del Estero. It was lowest in the area of Buenos Aires and in the north-central region of Santa Fé. Average Fisher's alpha for municipalities was 358; for districts, it was 422; and for Argentina as a unit, it was 602. The geographical distribution of alpha in 541 municipalities, high in the east and lower in the west of the country, is compatible with the settlement in the 20th century of subsequent waves of immigrants moving from the North Atlantic coast toward the foot of the Andes and toward the south. The present structure of Argentina indicates that migration dominates over drift. 相似文献
12.
Lyophilised, irradiated bone allografts available for the first time in the country from the Tata Memorial Hospital Tissue
Bank were used in 30 paediatric patients from January 2001 to August 2004. They included 20 patients of scoliosis of various
origin and ten with assorted orthopaedic conditions including one congenital kyphosis, two Pott’s spine, one Perthes disease,
one developmental dysplasia of the hip (DDH), one infective non-union, one fibrous dysplasia and three with bone defects either
due to trauma, a cyst or removal of hardware. Morsellised allograft was used in 28 patients. In those␣cases of scoliosis in
which ribs were resected out during costectomy, the morsellised allograft was␣mixed with morsellised rib autograft. Non-morsellised
femoral head grafts were used in two patients, one a case of varus open derotation osteotomy in Perthes disease and the other
an acetabuloplasty in DDH. Patients were followed at intervals of 8–12 weeks and radiological evaluation was done periodically.
The follow up period ranged from 1 to 4 years post surgery. All patients with scoliosis showed excellent union at the grafting
site with non-progression of curve and no signs of loosening at implant site. The two patients, in whom non-morsellised femoral
head grafts were used, both showed incorporation of the graft with good fusion within a 4 month period. None of the patient
had infection, non-union, pseudoarthrosis, fracture at the graft site, or any other complication. 相似文献
13.
14.
Molecular resolution of marine turtle stock composition in fishery bycatch: a case study in the Mediterranean 总被引:11,自引:1,他引:11
L. LAURENT P. CASALE M. N. BRADAI B. J. GODLEY G. GEROSA§ A. C. BRODERICK W. SCHROTH B. SCHIERWATER A. M. LEVY D. FREGGI E. M. ABD EL-MAWLA D. A. HADOUD H. E. GOMATI M. DOMINGO M. HADJICHRISTOPHOROU L. KORNARAKY F. DEMIRAYAK & CH. GAUTIER 《Molecular ecology》1998,7(11):1529-1542
Based on an extensive sampling regime from both nesting populations and bycatch, frequency analyses of mitochondrial (mt) DNA control region haplotypes in the Mediterranean were used to assess the genetic structure and stock composition of the loggerhead sea turtle, Caretta caretta, in different marine fisheries. The analyses show the following. (i) In drifting longline fisheries working in Mediterranean pelagic habitats 53–55% of turtles caught originated from the Mediterranean stock; (ii) In bottom-trawl fisheries all turtle bycatch is derived from this regional stock; (iii) This regional stock contribution to fishery bycatch suggests that the population size of the Mediterranean loggerhead nesting population is significantly larger than previously thought. This is consistent with a recent holistic estimate based on the discovery of a large rookery in Libya. (iv) Present impact of fishery-related mortality on the Mediterranean nesting population is probably incompatible with its long-term conservation. Sea turtle conservation regulations are urgently needed for the Mediterranean fisheries. (v) The significant divergence of mtDNA haplotype frequencies of the Turkish loggerhead colonies define this nesting population as a particularly important management unit. Large immature and adult stages from this management unit seem to be harvested predominantly by Egyptian fisheries. (vi) Combined with other data, our findings suggest that all the nesting populations in the Mediterranean should be considered as management units sharing immature pelagic habitats throughout the Mediterranean (and possibly the eastern Atlantic), with distinct and more localized benthic feeding habitats in the eastern basin used by large immatures and adults. (vii) Between the strict oceanic pelagic and the benthic stages, immature turtles appear to live through an intermediate neritic stage, in which they switch between pelagic and benthic foods. 相似文献
15.
Recent theoretical studies have suggested that host range in herbivorous insects may be more restricted by constraints on information processing on the ovipositing females than by trade-offs in larval feeding efficiency. We have investigated if females from polyphagous species have to pay for their ability to localize and evaluate plants from different species with a lower ability to discriminate between conspecific host plants with differences in quality. Females of the monophagous butterflies Polygonia satyrus, Vanessa indica and Inachis io and the polyphagous P. c-album and Cynthia cardui (all in Lepidoptera, Nymphalidae) were given a simultaneous choice of stinging nettles (Urtica dioica) of different quality. In addition, the same choice trial was given to females from two populations of P. c-album with different degrees of specificity. As predicted from the information processing hypothesis, all specialists discriminated significantly against the bad quality nettle, whereas the generalists laid an equal amount of eggs on both types of nettle. There were no corresponding differences between specialist and generalist larvae in their ability to utilize poor quality leaves. Our study therefore suggests that female host-searching behaviour plays an important role in determining host plant range. 相似文献
16.
U. M. COWGILL B. D. LANDENBERGER 《Botanical journal of the Linnean Society. Linnean Society of London》1992,109(2):223-234
COWGILL, U. M. & LANDENBERGER, B.D., 1992. The chemical composition of Astragalus: a comparison of seleniferous and non-seleniferous plants growing side by side. This paper describes how non-seleniferous plant species coexist with seleniferous ones and what chemical changes occur in non-seleniferous species that allow the toleration of large quantities of volatilized Se-bearing compounds. These compounds are known for their phytotoxicity as well as for their toxicity to mammals and insects. Twenty-three sites (Colorado, Utah, New Mexico, U.S.A.) were examined over a 6-year period. Plants collected from these sites were divided into four groups: seleniferous astragali, seleniferous Brassicaceae, non-seleniferous astragali and non-seleniferous associated genera. Furthermore, it was possible to categorize these sites: Type 1 sites supported all four groups of plants, Type 2 sites contained only seleniferous astragali, whereas Type 3 sites sustained only non-seleniferous astragali. When concentrations of Cu, Zn (P <0.0001), Si (P<0.02), As, Pb (P<0.03) and Cs (P<0.05) were measured, the values for those seleniferous astragali that coexisted with other species were significantly different from the values found for those seleniferous astragali that grew alone. There were four areas that in some years supported all four groups of plants (Type 1 site) and in other years contained only seleniferous astragali. In this way, the latter may be used as a chemical control for the former. The seleniferous astragali collected at Type 1 sites always contained more Cu, As, Si and Pb than the solitary astragali of Type 2 sites. When seleniferous astragali of Type 1 sites that support all four groups of plants develop in a year where the usually associated species of past years are absent, they contain in their tissues concentrations of Cu, As, Si, Pb, Zn and Cs typical of Type 2 sites where the seleniferous astragali grew alone. Non-seleniferous astragali of Type 1 sites that support all four groups of plants have a chemical composition that differs significantly in the quantity of 15 elements from non-seleniferous astragali of Type 3 sites where the latter grew alone. Since allelochemicals such as phenolic acids and flavonoids are well known to be able to alter mineral absorption by plants and since the astragali are known to produce such substances, it is suggested that the possible production of phenolic acids and flavonoids may permit coexistence of seleniferous plants with non-seleniferous ones and thus explain the chemical differences among the plants of the four types of sites. 相似文献
17.
Uemoto Y Soma Y Sato S Ishida M Shibata T Kadowaki H Kobayashi E Suzuki K 《Animal genetics》2012,43(1):27-34
The fatty acid composition and melting point of fatty tissue are among the most important economic traits in pig breeding because of their influence on the eating quality of meat. Identifying the quantitative trait locus (QTL) of these traits may help reveal the genetic structure of fatty acid composition and the melting point of fatty tissue and improve meat-quality traits by marker-assisted selection. We conducted whole-genome QTL analysis for fatty acid composition and melting point of inner and outer subcutaneous fat and inter- and intramuscular fat in a purebred Duroc population. A total of 129 markers were genotyped and used for QTL analysis. For fatty acid compositions of inner and outer subcutaneous fat, three significant QTL and 17 suggestive QTL were detected on SSC2, 4, 6, 8, 9, 10, 11, 12, 14 and 18. For the melting point of inner and outer subcutaneous fat, two significant QTL were detected on the same region of SSC14. For fatty acid compositions of inter- and intramuscular fat, five significant QTL and 13 suggestive QTL were detected on SSC2, 4, 6, 8, 9, 10, 14 and 15. On SSC14, significant QTL for C18:0 and C18:1 of outer subcutaneous fat and intramuscular fat, and melting point of subcutaneous fat, which had high likelihood of odds (LOD) scores (2.67-5.78), were detected in the same region. This study determined QTL affecting fatty acid composition and melting point of different fat tissues in purebred Duroc pigs. 相似文献
18.
H. Miliou 《Hydrobiologia》1992,232(3):201-209
The harpacticoid copepod Tisbe holothuriae Humes was reared for several generations under different photoperiods (white light) and spectral quality (continuous illumination).
The main life cycle parameters were measured and demographic variables were determined. Development time was retarded under
green wavelengths and at photoperiods different from LD 12:12, especially under continuous white light. Total body length
of females and males was shortest under LD 12:12 and longest under constant dark. Photoperiods different from LD 12:12 prolonged
the interval between broods of egg sacs. Short photoperiods caused higher abortion rate, while long photoperiods retarded
the maturation time of the egg sacs. Red wavelengths stimulated the abortion rate. Photoperiod LD 12:12 and blue wavelengths
increased the production of offspring and the life span of females. Highest intrinsic rates of natural increase were estimated
under LD 12:12 (rm =0.304) and blue wavelengths (rm = 0.254). These light conditions proved the most favourable for rearing Tisbe holothuriae. 相似文献
19.
Ants are some of the most abundant and ecologically successful terrestrial organisms, and invasive ants rank among the most damaging invasive species. The Argentine ant is a particularly well-studied invader, in part because of the extreme social structure of introduced populations, known as unicoloniality. Unicolonial ants form geographically vast supercolonies, within which territorial behaviour and intraspecific aggression are absent. Because the extreme social structure of introduced populations arises from the widespread acceptance of conspecifics, understanding how this colonymate recognition occurs is key to explaining their success as invaders. Here, we present analyses of Argentine ant recognition cues (cuticular hydrocarbons) and population genetic characteristics from 25 sites across four continents and the Hawaiian Islands. By examining both hydrocarbon profiles and microsatellite genotypes in the same individual ants, we show that native and introduced populations differ in several respects. Both individual workers and groups of nestmates in the introduced range possess less diverse chemical profiles than ants in the native range. As previous studies have reported, we also find that introduced populations possess much lower levels of genetic diversity than populations in the native range. Interestingly, the largest supercolonies on several continents are strikingly similar to each other, suggesting that they arose from a shared introduction pathway. This high similarity suggests that these geographically far-flung ants may still recognize and accept each other as colonymates, thus representing distant nodes of a single, widely distributed supercolony. These findings shed light on the behaviour and sociality of these unicolonial invaders, and pose new questions about the history and origins of introduced populations. 相似文献
20.
退化红壤丘陵区森林凋落物初始化学组成与分解速率的关系 总被引:7,自引:1,他引:7
通过小盆+凋落袋控制试验,研究了我国南方退化红壤丘陵区8种森林凋落物和4种混合凋落物初始化学组成与分解速率的关系.结果表明:阔叶凋落物中的氮、磷、钾、镁含量显著高于针叶凋落物,木质素、碳含量显著低于针叶凋落物;凋落物分解速率与凋落物初始氮、磷、钾、镁含量呈显著正相关,与凋落物初始碳、木质素含量以及木质素/氮、木质素/磷和碳/磷值呈显著负相关;木质素含量解释了凋落物分解速率变异的54.3%,是影响分解速率的最关键因子,凋落物碳、氮、磷含量也与分解速率密切相关,它们与木质素含量一起可解释分解速率变异的81.4%.在退化红壤丘陵区植被恢复过程中,低木质素含量、高氮磷含量的阔叶物种的引入有利于加速凋落物的分解速率和土壤肥力的恢复进程. 相似文献